S
M
T
W
T
F
S
26
97°
75°
27
98°
73°
28
98°
76°
29
98°
77°
30
101°
78°
31
99°
76°
1
101°
75°
2
101°
77°
3
100°
69°
4
99°
78°
5
98°
75°
6
100°
76°
7
99°
74°
8
98°
72°
9
99°
73°
10
97°
74°
11
100°
77°
12
101°
79°
13
101°
77°
14
99°
75°
15
101°
78°
16
101°
69°
17
102°
75°
18
101°
71°
19
101°
75°
20
103°
71°
21
103°
72°
22
105°
72°
23
103°
69°
24
103°
73°
25
101°
69°
26
102°
73°
27
103°
75°
28
100°
72°
29
99°
71°
30
99°
73°
31
99°
73°
1
100°
73°
2
103°
76°
3
101°
79°
4
93°
76°
5
100°
72°
Temperature Graph
°F
Avg. Hi
Avg. Lo
Actual Hi
Actual Lo
Forecast Hi
Forecast Lo
August Weather in San Marcos
San Marcos's August 2026 forecast shows daily high temperatures ranging from ° to °, with overnight lows between ° and °. The average high for August is ° with an average low of °. AccuWeather's monthly forecast extends further ahead than any other source, with day-by-day RealFeel® Temperatures giving a complete picture of how August weather will actually feel in San Marcos. See also: September | October | November.
